Knife assemblies for winding machines

ABSTRACT

A knife assembly for cutting strip material such as plastics film or tape during a winding operation whereby the trailing end of the severed strip is wrapped onto the completed reel and the leading end of the severed strip is wrapped on to a new core. Preferably, a backing member is movable into a position behind the strip, a knife or knives are moved into engagement with the strip and then transversely of the strip to effect the cutting action, brush means wraps the trailing end on to the completed reel, and roller means wraps the leading end on to a new core.

United States Paten 11 1 Burnage 1 July 10, 1973 [54] KNIFE ASSEMBLIES FOR WINDING 3,189,293 6/1965 Prager 242/56 R X MACHINES 2,723,717 11/1955 Clark 242/56 R 2,668,675 2/1954 Wolfe 242/56 A [75] Inventor: David Burnage, Bromham, England [73] A J h D be C I FOREIGN PATENTS OR APPLICATIONS ss1gnee: o ii men rg ompany nc.

Clifton, NJ 1,055,801 4/1959 Germany 242/56 A [22] Filed: Nov. 15, 1971 Primary Examiner-George F. Mautz Assistant Examiner-Edward J. McCarthy [21] Appl' 198350 Attorney-Rudolph J. Jurick [30] Foreign Application Priority Data 57 ABSTRACT NOV. 16, I970 Great Britain 54,453/70 A knife for cutting Strip materia such as p tics film or tape during a winding operation whereby [52] 242/56 Zi the trailing end of the severed strip is wrapped onto the 4 26 completed reel and the leading end of the severed strip [51] Int. Cl B6 h 9/ is wrapped on to a new con," [58] Field of Search 242/56 A, 56 R, 56.6;

Preferably, a backing member is movable into a 557 position behind the strip, a knife or knives are moved [56] References Cited iriito engatgengnttitigth thte strip and tgen Lransversely of e 5 up 0 e ec e cu mg ac ion, rus means wraps UNITED STATES PATENTS the trailing end on to the completed reel, and roller 3,472,462 10/1969 Young 242/56 R means wraps the leading end on to a new com 2,860,839 11/1958 Bower 242/56 A 4/ 1970 Wheeler 83/508 12 Claims, 5 Drawing Figures PATENIEDJUL 1o ms v r Y 3.744.730

SHEET- 1 UF 5 F/az Pmmnzm m I 3.744.730

SHEET 5 [IF 5 KNIFE ASSEMBLIES FOR WINDING MACHINES BACKGROUND OF THE INVENTION: FIELD OF THE INVENTION This invention relates to the cutting of strip material being wound on a core or cores mounted on a mandrel, for example in a turret winder, and is concerned primarily with a knife assembly which operates to cut such strip material when the cores on a mandrel are fully wound and it is desired to transfer the winding operation to a new set of cores.

The invention is particularly applicable to the winding of press-sensitive vinyl electrical tape at the output side of a tape coating machine, although it is not limited to use with strip material of this type.

BACKGROUND OF THE INVENTION: DESCRIPTION OF THE PRIOR ART In the operation of conventional slitting machinery, sheet material, for example a large reel of plastics film, metal foil, or other web material, is passed through a series of guide rolls and smoothing rolls and is slit by a plurality of slitting knives which divide the web longitudinally across its width into a number of smaller strips. It is standard practice in modern slitting machinery to wind the resultant slit strips upon individual cores mounted on mandrels supported at each end by rotationally indexable turrets. As the cores on a mandrel become fully wound so a transfer operation is initiated whereby the slit strips are severed and their leading ends are transferred to empty cores on a succeeding mandrel.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a knife assembly which by its construction and manner of operation will sever the slit strips of a web, or will sever a single web of substantial width, and which will ensure that the trailing ends of upwrapped material on the wound reels are wrapped smoothly on to the completed reels.

It is a further object of the invention to provide a knife assembly which willensure also that the leading ends of the severed strips are smoothly wrapped on to the new empty cores.

In accordance with one aspect of the present invention there is provided a method of severing a strip of material trailing from a reel of such material wound on a core in a turret winding machine, comprising the steps of raising the wound core from a winding station, indexing the turrets to bring a new core into the wind ing station, moving a backing member into a position behind one surface of the strip between the new core and the raised core, moving a score knife mounted on a knife carriage into inpingement with the other surface of the strip, and effecting movement of the knife carriage transversely of the line of movement of the strip to effect severing of the strip.

Preferably, and when used with a strip which is adhesive on one surface, the method further includes retracting the backing member and causing wrapping means to wrap the trailing end of the severed strip around the completed reel.

The method also preferably includes causing further wrapping means to wrap the leading end of the severed strip around the new core.

In accordance with another aspect of the invention there is provided a knife assembly for a winding machine comprising apair of relatively displaceable parts, one partbeing'movable into a position behind one surface ofa strip of material to be cut and including a backing member against which cutting is effected, and the other part being displaceable towards and away from thebacking member, the latter part comprising a knife carriage provided with at least one score knife, and means operative to effect displacement of the score knife transversely of the line of movement of the I strip.

Preferably, the assembly includes a brush carriage associated with the knife carriage and carrying brush means operative to wrap the trailing end of the cut strip around a completed reel, and contact roller means which can beactuated to effect wrapping of the leading end of the cut strip around an empty winding core.

Preferably, the assembly includes a plurality of score knives arranged in series along the knife carriage and resiliently mounted on the knife carriage.

In order that the invention may be more fully understood a preferred embodiment of knife assembly in accordance with the invention will now be described by way of example and with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic side elevational view, partly in section, showing the winding machine turret and the two relatively movable parts of the knife assembly;

FIG. 2 is a plan view of the knife assembly of FIG. 1 looking in the direction of the arrow A in FIG. 1;

FIG. 3 is a sectional view taken along the line III-III of FIG. 1;

FIG. 4 is a partial sectional view taken along the line IV-IV of FIG. 2; and,

FIG. 5 is a partial view taken along the line of the arrow B in FIG. 1 illustrating the hydraulic latch for one of the lower pivoting arms of the knife assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring first to FIG. 1, there is shown in broken outline a turret 10 of a turret winding machine. The turret l0 and a corresponding turret on the other side of the winding machine are each provided with a plurality of sockets around their circumference, these sockets holding mandrels extending between the turrets and each provided with a plurality of cores spaced along their length and on which strips of material resulting from slitting of a wide web of material are arranged to be wound. The turret l0 and its partner are indexable rotationally whereby the mandrels and the cores carried on the mandrels are moved in a circular path. One such core is indicated at 12 in its empty state at the winding station before winding of strip material thereon. This core 12 is shown in the actual position which it occupies during winding of the strip material on it.

Positioned below the core 12 are a pair of pivotable .arms, one at each side of the turret winding machine,

and only one of which is shown in FIG. 1 at 14. The arm 14 is pivoted at 16 on a rigid part of the machine structure, and during the winding of the strip material on the core 12 the arm 14 is pivoted downwardly fromthe position shown in FIG. 1 to a lower, inactive position. The

pivoting movement can be controlled hydraulically or pneumatically and for this purpose a piston rod 18 'is provided, the piston rod having an enlarged end portion 20 coupled to the arm 14 and having its other end terminating in a piston displaceable in a cylinder (not shown). A support beam 22 extends transversely of the machine between the two pivotable arms 14 and carries a bracket 24 on its one face. The bracket 24 has a support member 26 secured thereto and secured to the latter is a backing member 28 which extends across the width of the machine and which is made of a suitably hardened material such as steel.

Below and adjacent to the pivotable arms 14 are provided hydraulically or pneumatically operated locks adapted to hold the pivotable arms 14 securely when pivoted to their raised, active position as shown in FIG. 1. These locks are shown in particular detail in FIG. 5. A cylinder bracket 30 is secured to the rigid body of the turret winding machine at each side thereof and carries a cylinder 32. The cylinder 32 is fitted with an end cap 34 and a piston 36 having an associated piston rod 38 is reciprocably movable within the cylinder 32. O-ring seals 40 and 42 provide appropriate sealing means between the cylinder 32 on the one hand and the piston 36 and piston rod 38 respectively on the other hand. The piston rod 38 of each lock is arranged to engage, when extended from the cylinder 32, in a hole 44 formed in a projecting lug 46 (FIG. 1) on the arm 14.

Above the pivotable arms 14 is the upper portion of the knife assembly which, as shown in FIG. 1, is movable in an are defined by curved slots 48 provided in the side walls of the turret winding machine. This upper portion of the knife assembly comprises a knife carriage 50, a knife carriage base 52, and a brush carriage 54. The knife carriage base 52 is provided with support brackets 56a and 56b (FIG. 2) at opposite ends thereof, and it is by means of these support brackets 56a, 56b that the upper knife assembly is movable in its arcuate slots 48. Flat cage bearings 58 are recessed into the upper surface of the knife carriage base 52 to permit a sliding motion of the knife carriage 50 relative to the knife carriage base 52 in the direction transverse to the line of movement of the strips being wound on the cores. This movement of the knife carriage 50 is effected pneumatically, or possibly hydraulically in certain circumstances. A pneumatic cylinder 60 is mounted on the knife carriage base 52 and the associated piston rod 62 is coupled by a pin 64 to a pusher block 66 which is fixedly mounted on the knife carriage 50. Thus, extension or retraction of the piston rod 62 will cause a transverse movement of the knife carriage 50. The rear face of the knife carriage 50 has a downwardly extending bracket 68 secured thereto with a pair of trip limit switches 70 mounted at the lower edge thereof. The actuation of the pneumatic cylinder 60 is controlled by the limit switches 70 through conventional external electrical circuitry which is not shown. The knife carriage 50 is further provided with a pluralityof elongated slots 72 therethrough and extending transversely of the direction of movement of the strips being wound on the cores. These elongated slots 72 receive rollers 74 which are mounted in the knife carriage base 52. The knife carriage 50 is also provided with further elongated slots 76 parallel to the slots 72. A pair of brackets 78 extend upwardly through the slots 76, the brackets 78 being secured relative to the knife carriage base 52. These brackets 78 provide further guidance forthe knife carriage 50 during its transverse movement. Further brackets 80 similar to the brackets 78 are also secured to the knife carriage base 52 at its rear edge and in alignment with the brackets 78. The brackets 78 and 80 each carry rollers 82 which are arranged to engage the upper surface of the knife carriage 50.

The structural details of the knife carriage 50 are most clearly seen in FIGS. 1 and 4. As mentioned above, the knife carriage 50 is only capable of a reciprocating transverse movement. The knife carriage 50 is provided with nine circular knives 84 of suitable material such as hardened steel. The knives 84 are mounted in a line along the leading edge of the knife carriage 50. Each knife 84 is mounted on a shaft 86 and is provided at its lower face with a washer 88, a Belleville washer 90, a further washer 92, and a circlip 94. Each knife 84 is mounted by a combination of fixed and movable dovetails 96 to the main knife carriage member which rides upon the knife carriage base 52. Each knife 84 is secured to its dovetail 96 by screws 98. Each dovetail 96 is restrained against forward movement by a grub screw 100 passing down through the front end portion of the main knife carriage member. This grub screw 98 is screwed hard down on to the dovetail 96 and then unscrewed through one revolution. The knives 84 are resiliently mounted to compensate for small variations in their diameters. Thus, each dovetail 96 is fitted at its rear face with a dowel pin 102, the other end of which is arranged to slide into a recess 103 formed in the main knife carriage member. Each dowel pin 102 is surrounded by a stack of Belleville washers 104 to provide the desired resilient bias urging the dovetails 96 and thus the knives 84 forward until restrained by the projecting screws 100. The dovetails 96 hold the respective knives and restrain their movement so that it is always in the direction of the spring force.

The brush carriage 54 is shown more particularly in FIGS. 1, 2 and 4. It comprises a plate member 106 whose plan outline is best seen in FIG. 2. This plate member 106 includes two rearwardly extending arms adjacent to its oppositeends and two forwardly extending fingers 108 at its extreme outside edges. Along the front edge of the brush carriage between the fingers 108 is held a brush 110 clamped between a pair of bars 112 and 114. The bars 112, 114 are screwed together and to the plate member 106 so that the brush 110 extends perpendicular to the top surface of the brush carriage 54. The brush carriage 54 is arranged for movement towards the left as shown in FIG. 4, Le. parallel to the line of movement of the strip material being wound on the cores. For this purpose the plate member 106 is provided at its rear comers with a pair of brackets 116 to which are secured pairs of vertically extending cam followers 118 and pairs of horizontally extending cam followers 120. The cam followers 118 are arranged to slide along lateral faces of cam guides 122 and the cam followers are arranged to slide within grooves formed in said lateral faces of the cam guides 122. Also secured to the rearwardly extending arms of the plate member 106 are a pair of brackets 124 which project rearwardly of the brush carriage. The rearward end of each of these brackets 124 carries a grooved pin 126 to which is secured one end of a spring 128. The other end of each of the springs 128 is secured to a further grooved pin 130 projecting from the brackets 78 which interconnect the knife carriage 50 and the knife carriage base 52. The brackets 124 are adjustably secured to the plate member 106 by detachable nuts so that the spring tension can be adjusted as desired.

Mounted below the knives 84 and below the knife carriage base 52 is a tape roll-on mechanism which is shown in FIGS. 1 and 3. A pneumatic cylinder 132 is secured by a bracket to the knife carriage base 52, and its piston rod 134 extends through a spacer 136 and is coupled through a pin 138 to a horizontal tie bar 140. Each end of the tie bar 140 is fitted with a flanged bush 141 which carries links 142 and 144. The two links 144 provide a connection to opposite ends of a tape contact roller 146. The links 142 and 144 each carry an inwardly projecting grooved pin 148 and 150 respectively, and at each side of the mechanism between the pins 148 and 150 is secured a spring 152 which, as shown in FIG. 1, passes beneath the tie bar 140. These springs 152 therefore exert a downward component of force on the contact roller 146. The tape roll-on mechanism is further supported beneath the knives 84 by brackets 154 which are secured to the underside of the knife carriage base 52. I

The sequence of movements in the operation of the knife assembly is as follows. When a series of cores mounted on a mandrel have been fully wound, for example with adhesive tape strips, the completed reels are raised on their mandrel from the turret by means of lifting arms (not shown) to a position as indicated at 160 in broken outline in FIG. 1 where the tape strips, indicated at 162, extend across the position where the backing member 28 and the knives 84 will meet. At this time the pivotable arms 14 and the upper portion of the knife assembly which includes the knives themselves are both pivoted away from the region of the tape strips, the arms 14 being in their lower inactive position and the upper portion of the knife assembly being raised to the top of the arcuate slots 48. After raising the completed reels clear of the turrets the turrets are indexed, thus bringing a new set of empty cores into the position indicated at 12 in FIG. 1, whereby the new cores come into contact with the adhesive side of the strips. The arms 14 are then pivoted in a clockwise sense as viewed in FIG. 1 to bring the backing member 28 around behind the new cores and into contact with the tape strips at a position between the completed reels and the new cores. The locking mechanism for the arms 14 which is illustrated in FIG. 5 is then actuated and the piston rods 38 are extended into latching engagement in the holes 44 in the lugs 46 of the arms. This locks the score strip 28 rigidly in position.

The upper part of the knife assembly is then lowered in its arcuate path defined by the slots 48 down towards the tape strips until the knives 84 abut the backing member 28 with the tape strips running therebetween. As the knives 84 are being lowered into this position the forwardly projecting fingers 108 of the brush carriage 54 strike the bracket 26 and cause the brush carriage 54 to slide rearwardly relative to the knife carriage 50, thereby tensioning the springs 128. The knife assembly is then substantially in the position shown in FIG. 1 with the knives 84 impinging against the tape strips.

The piston and cylinder mechanism 60, 62 is then actuated to cause extension of the piston rod 62 and consequent sideways movement of the knife carriage guided by the various cam followers. The knife carriage 50 is moved sideways through a distance slightly greater thanthe diameter of one knife 84, for example about 3% inches, thereby cutting the tape strips. The locks holding the pivotable arms 14 are then released and the arms 14 are then retracted, thereby causing the backing member 28 to move away from the cutting knives 84. As the adhesive surface of the tape strips faces towards the backing member 28 the backing member in its retracting movement pulls the leading ends of the severed strips downwardly towards the new cores. The cylinder 132 is then actuated to operate the tape roll-on mechanism whereby the contact roller 146 is pushed forward over the cores 12 thus completing the wrapping of the severed leading ends of the strips on to the new cores.

As the arms 14 are pivoted downwardly and the backing member 28 is retracted the rearward force exerted on the fingers 108 of the brush carriage is removed and the stressed springs 128 cause a forward sliding movement of the brush carriage 54 relative to the knife carriage 50. This results in a forward movement of the brush which thereby wraps the trailing ends of the severed strips around the completed reels.

The cylinder 132 is then controlled so as to retract its piston rod 134 and thereby pull the contact roller 146 back to its initial position. The contact roller 146 is mounted on its linkage in such manner that it always returns to the same position. Finally, the upper portion of the knife assembly comprising the knife carriage base 52, the knife carriage 50 and the brush carriage 54 is retracted to .its rest position at the top of the slots 48 and winding of the tape strips on the new cores is commenced.

In a slightly modified construction, the movement of the brush carriage 54 is controlled in a different manner. In this alternative embodiment the brush carriage is held in its back or retracted position by a pneumatic cylinder which is coupled to the carriage by a chain. The signal which causes the contact roller 146 to move over the new core now also causes the pneumatic cylinder to release tension in the chain. Springs, like the springs 128 in the first embodiment, cause the brush carriage to move forward, thereby brushing the trailing ends of the tapes on to the completed reels. On completion of these two movements, both cylinders reverse, the contact roller 146 returns to its parked position, and the brush returns against the spring force by the action of the chain and penumatic cylinder.

Although the foregoing description has been concerned with the cutting of a plurality of tape strips at the output side of a slitting machine, the knife assembly of the present invention can equally well be adapted for use in severing a single wide web of material. More over, the materials of which the knives 84 and the backing member 28 are made may be of any suitable form depending upon the nature of the strips or strip to be severed.

It will thus be appreciated that the knife assembly of the present invention provides an efficient means of severing strip material with great precision while also providing means for wrapping the leading and trailing ends of the severed strips around the new cores and the completed reels respectively.

I claim:

1. A method of severing a strip of material trailing from a reel of such material wound on a core in a winding station of a turret winding machine, comprising the steps of indexing the turrets to bring a new core into the winding station, moving a backing member into a position behind one surface of the strip between the new core and the wound core, moving a score knife mounted on a knife carriage into impingement with the other surface of the strip, and effecting movement of the knife carriage transversely of the line of movement of the strip to effect severing of the strip.

2. A method as claimed in claim 1', in which the strip is adhesive on one surface, and which further includes retracting the backing member and causing wrapping means to wrap the trailing end of the severed strip around the completed reel.

3. A method as claimed in claim 2, which includes causing further wrapping means to wrap the leading end of the severed strip around the new core.

4. A method as claimed in claim 3, wherein the trailing end of the severed strip is brushed on to the completed reel and the leading end of the severed strip is rolled on to the new core.

5. A knife assembly for a winding machine comprising a pair of relatively displaceable parts, one part being movable into a position behind one surface of a strip of material to be cut and including a backing member against which cutting is effected, and the other part disposed in front of the strip and being displaceable towards and away from the backing member, the latter part comprising a knife carriage provided with at least one score knife, and means operative to effect displacement of the score knife transversely of the line of movement of the strip.

6. A knife assembly as claimed in claim 5, which includes a brush carriage associated with the knife carriage and carrying brush means operative to wrap the trailing end of the cut strip around a completed reel.

7. A knife assembly as claimed in claim 6, in which the brush carriage is held in an inactive position by restraining means when the said one part of the assembly is in said cutting position behind the strip of material, and in which upon retraction of said one part the brush carriage moves towards the strip under a spring force to bring the brush means into contact with the trailing end of the cut strip.

8. A knife assembly as claimed in claim 5, which includes contact roller means which can be actuated to effect wrapping of the leading end of the cut strip around an empty winding core.

9. A knife assembly as claimed in claim 8, in which the contact roller means comprises a roller which is normally restrained in an inactive position but which when actuated moves under a spring force to perform its wrapping function.

10. A knife assembly as claimed in claim 5, which includes a plurality of score knives arranged in series along the knife carriage and resiliently mounted on the knife carriage.

11. A knife assembly as claimed in claim 10, in which the score knives are circular.

12. A knife assembly as claimed in claim 5, in which said one part of the assembly comprises a pair of pivotable arms carrying the backing member, and said other part of the assembly is also displaceable along an arcuate path. 

1. A method of severing a strip of material trailing from a reel of such material wound on a core in a winding station of a turret winding machine, comprising the steps of indexing the turrets to bring a new core into the winding station, moving a backing member into a position behind one surface of the strip between the new core and the wound core, moving a score knife mounted on a knife carriage into impingement with the other surface of the strip, and effecting movement of the knife carriage transversely of the line of movement of the strip to effect severing of the strip.
 2. A method as claimed in claim 1, in which the strip is adhesive on one surface, and which further includes retracting the backing member and causing wrapping means to wrap the trailing end of the severed strip around the completed reel.
 3. A method as claimed in claim 2, which includes causing further wrapping means to wrap the leading end of the severed strip around the new core.
 4. A method as claimed in claim 3, wherein the trailing end of the severed strip is brushed on to the completed reel and the leading end of the severed strip is rolled on to the new core.
 5. A knife assembly for a winding machine comprising a pair of relatively displaceable parts, one part being movable into a position behind one surface of a strip of material to be cut and including a backing member against which cutting is effected, and the other part disposed in front of the strip and being displaceable towards and away from the backing member, the latter part comprising a knife carriage provided with at least one score knife, and means operative to effect displacement of the score knife transversely of the line of movement of the strip.
 6. A knife assembly as claimed in claim 5, which includes a brush carriage associated with the knife carriage and carrying brush means operative to wrap the trailing end of the cut strip around a completed reel.
 7. A knife assembly as claimed in claim 6, in which the brush carriage is held in an inactive position by restraining means when the said one part of the assembly is in said cutting position behind the strip of material, and in which upon retraction of said one part the brush carriage moves towards the strip under a spring force to bring the brush means into contact with the trailing end of the cut strip.
 8. A knife assembly as claimed in claim 5, which includes contact roller means which can be actuated to effect wrapping of the leaDing end of the cut strip around an empty winding core.
 9. A knife assembly as claimed in claim 8, in which the contact roller means comprises a roller which is normally restrained in an inactive position but which when actuated moves under a spring force to perform its wrapping function.
 10. A knife assembly as claimed in claim 5, which includes a plurality of score knives arranged in series along the knife carriage and resiliently mounted on the knife carriage.
 11. A knife assembly as claimed in claim 10, in which the score knives are circular.
 12. A knife assembly as claimed in claim 5, in which said one part of the assembly comprises a pair of pivotable arms carrying the backing member, and said other part of the assembly is also displaceable along an arcuate path. 